Large Eddy Simulation on the Fluid Flow, Solidification and Entrapment of Inclusions in the Steel Along the Full Continuous Casting Slab Strand

Three-dimensional mathematical models on the fluid flow, solidification, motion and entrapment of inclusions in an actual vertical-bending continuous casting (CC) strand were developed. The large eddy simulation turbulent model coupled with Lagrangian discrete phase model was used to investigate the instantaneous flow field, solidification and transport of nonmetallic inclusions in the strand. Inclusions were assumed to be captured by the solidification front where the liquid fraction and the fluid flow speed are less than 0.6m/s and 0.07m/s, respectively. The removal and entrapment of inclusions were achieved using the user-defined function. An industrial measurement of a breakout continuous casting shell and an inclusion detection using ASPEX were employed to validate the solidification calculation and inclusion captured criteria, respectively. The spacial distribution of captured nonmetallic inclusions in the cross-section of the CC slab was predicted, indicating that the removal fraction of inclusions larger than 30m increased with the increasing inclusion size. Two accumulation peaks of inclusions along the thickness of the CC slab were predicted. One was located at the centerline of the slab thickness and the other was located at 1/4 thickness from the loose side. In addition, an enrichment zone of inclusions in the slab existed for each size of inclusions.